Attachment for grinding-machines.



M5.-=0. CROSS. ATTACHMENT FOR GRINDING MACHINES.

APPLICATION FILED DEC. I4, 1914.

1 1 47,2 1 4:. Patented July 20, 1915.

2 SHEETSSHEET 1,

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WITNESSES:

m AMW W 2 4/ Wail M. 0. CROSS.

ATTACHMENT FOR GRINDING MACHINES.

APPLICATION FILED DEC. 14. 1914.

1,147,214. Patented July 20, 1915.

2 SHEETS-SHEET 2.

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ATTACHMENT F03. GBINDING-MACHINES.

arcia.

Specification of Eetters Patent.

Application filed December 14, 1914. Serial No. 877,071.

To all whom it may concern:

Be it known that I, MILTON 0..CROSS, a citizen of the United States, residing at Detroit, county of Wayne, State ofMichigan,

have invented aeertain new and useful Improvement in .eittachments for Grinding- Machines andkleclare the following to be a full, clear, and exact description of the same, such as will enable others skilled in the art to which it pertains to make and use the same, reference being had to the accompanying drawings, which form a part of this specification. This invention relates to attachments for grinding machines-for grinding hobs, millin cutters, spiral gears, worms, etc. 7

he device may be used with any grinder in which the bed is movable longitudinally, vertically, and transversely.

- The primary object of the invention is an appliance for, supporting the work to be operated uponby means of which it may be turned during the grinding operation to maintain a tooth of the blank in contact.

with the grinding wheel throughout its length and which is also adjustable to accommodate teeth lying at various angles or to operate on the threads of worms. The

grinding wheel has the form of the shank of the tooth or thread to be ground. I

A further object of the invention, resides in the means by which the work may be indexed through use of a master-gear, provision being made whereby various sizes 0 indexing gears may be employed.

An additional object is a device for the purpose described that is simple in construction, inexpens've to manufacture, and that is readily attac able to the machine to whlch These and other objects and the various novel features of construction are hereinafter more fully described and claimed and shown in the accompanying drawings m which- I Figure 1 is a plan view of a grinding machine showing my improved attachment.

Fig. 2 is a side elevation thereof. Fig. 3 is an end elevation part1 in section showing more clearly the indexing gear. Fig 4 1s a detail, artly in section, of the indexing device. ig. 5 is an end view ofthe attachment as arranged to operate on the-thread of the worm.

Similar characters refer to similar parts throughout thedrawings and specificatlon.

The base of the grinding machine is indlcated atl on which is carried a bed plate 2. It is to be understood'that this plate is movable both vertically and transversely as Patented duty 20, 1915.

well as longitudinally of the base as is usual with this general type of grinding machine. The means by which such movement or the bed plate may be produced are not here shown as they are now well known in the art. Removably mounted on the base at the rear thereof, as shown more particularly in Fig. 3, is the grinding wheel support 3 prof.

vided with calibrations 4 by means of which the grinding wheel 5 may be set at any desired angle in a horizontal plane. The grinding wheel is mounted on a shaft 6 carried in bearings with which the head is provided and a pulley 7 is secured to the shaft through the medium of which the giindin wheel is driven at the proper rate of spec The bed plate 2 has mounted thereon the usual head-stock 8 and tail-stock 9, both of which are provided with the usual center pins 10 and 11 for supporting the work holder inthe manner allowing it to be turned as hereinafter described. v

- The work holder consists of a shaft 12 slightly preferably tapered throughout its length (although not as shown)-and adapted to be supported between the center points 10 and 11 as shown more particularly in Figs. 1 and 2. This shaft is provided wlth a collar 13 near one end thereof and secured to the end of the shaft is a master-gear 14- by means of which the work maybe indexed.

so i

Between the collar 13 and the gear 14 is loosely mounted a wheel 15 having 'a central recess into which the master-gearextends as shown more particularly in Fig. 4. In therim of the wheel 15 is secured .a spring pressed plunger lfi-having an end normally engaging between the teeth of the mastermachine is provided a standard 19 adapted to receive a stem 20 to which a head 21 is secured. The stem is adjustable in the standard 19 to set the head at any height desired. The head also carries a shaft 22 provided with a hand-wheel 23 on the outer end and on the inner end is provided with a guide plate or bar 24: having a hub 25 adjacent'the head. As shown in Fig. 3, the head '21 and the hub 25 are calibrated in order that the guide bar may be set at any angle desired and the shaft then held from turning by means of the set screw 26 which binds the shaft in the head.

As may be seen in Figs. 1 and 2, the guide bar 24 extends longitudinally of the machine and parallel with the work and the arm 17 attached-to the wheel 15 rides on this guide bar. As before stated the bed plate 2 moves longitudinally of the base during the grinding operation, which movement causes the arm 17 to ride up and down the angularly positioned guide bar 24:, turning the workshaft 12 to such degree as is determined by the angle of the guide-bar. By setting the guide-bar at various angles it is evident that teeth having various angles as spiral gears, may be operated upon as it is only necessary to set the guide-bar to turn the shaft 12 either slowly or rapidly as the work may demand.

In operation the work holder and the work are set in the-machine and the bed set to travel a distance to allow the grinding wheel to pass out from the tooth at each end of the stroke, the bed moving first to the right and then returning, during both of which movements the grinding wheel is in engagement with the work. In the position of parts shown .in Fig. 2 and the work to be operated on, the bed plate at the beginning of its movement is at the left of the machine with the arm 17 at the lowest point on the guide, bar, as the bed moves toward the right the arm 17 rides up the guide-bar and turns the work at a speed determined by the angle thereof and as the grinding wheel rides out from engagement with the work the bed plate is reversed in its movement whereupon the grinding wheel engages the same tooth if further grinding is desired. During the return movement of the bed, the arm 1? is held in engagement with the guide-bar by reason of the pressure of the grinding wheel against the tooth of the work. At the finish of this stroke the work is indexed by hand by withdrawing the plungerlfi from between the teeth of the master-gear and the wheel 15 turned forward which raises the bar 17 from the guide bar 24, when the plunger is again set in the next succeeding tooth of the master-gear. The wheel 17 and master-gear are then turnedbackward until the. arm 17 engages the guide barwhich indexes the work one tooth. lit a single movement of the grind ing wheel across the shank of the toothis found suficient in some cases, the work may be indexed at both ends, of the stroke of the bed plate inthe same manner as above described.

In grinding the threads of worms and the like it is necessary for the Work holder to be turned a complete revolution or more, this may be readily accomplished in the manner indicated in F ig. 5, in which the wheel 15 is provided with a groove about which is ,wrapped a single turn of a'flexible wire 30. This wire has one end attached to a spring 31 secured to any convenient point as a bracket 32 on the-bed. The opposite end is attached to a'bell crank 33 pivoted one standard supported on the bed plate and movable therewith. The short arm of the bell crank rides on the guide bar 24: in the same manner as the arm 17 heretofore described. As the bed plate moves relative to the guide-bar the motion of the short arm is multiplied and the wire 30 rolls the work shaft to an extent greater than with the arm 17 directly fixed thereto as above described and thus work having threads with a very sharp pitch may be ground.

Having thus briefly described my invention its utility and mode of operation, what I claim is 1. In a grinding machine having a longitudinally movable bed and a grinding wheel capable of angular adjustment relative to the line of travel of the bed, a work holder revolubly supported by the bed, a stationary guide, and means on the holder engaging the guide whereby movement of the bed may Q turn the holder.

2. In a grinding machine having a longitudinally movable bed and a grinding wheel capable of angular adjustment horizontally relative to the line of travel of the bed, a

work holder revolubly supported by the bed, a guide angularly adjustable in a vertical plane, and means on the holder engaging the guide whereby movement of the bed may turn the holder.

guide-bar at the side of the bed, meanson' the holder engaging the bar whereby the holder may be turned during movement of the bed, and means for altering the angle of the bar relative to the line of travel of the work whereby said work may be turned or anem a tudinally movable bed and a grinding wheelcapable of angular adjustment in a horizontal plane, relative to the line of travel of the bed, a work holder comprising a work supporting shaft revolubly supported by the bed, a wheel lmsely mounted for rotation on the shaft, an indexing gear secured to the shaft, releasable means for securing the wheel, to the indexing gear, a guide bar adapted for angular adjustment in a vertical plane, and an arm on the loosely mounted wheel engaging the guide-bar by means of which the work-shaft is turned during -movement of the bed,

6. In a grinding machine having a longitudinally movable bed and a grinding wheel capable of angular adjustment horizontally relative to the line of travel of the bed, a Y work holder comprising a work supporting shaft revolubly supported by the bed, a

wheel loosely mounted on the shaft, an in work, and an arm. engaging the said guidebar and connected with the work holding device in such manner that movement of the arm relative to the guide bar turns the work holder. i

7. An attachment for grinding machines provided with a grinding wheel capable of "angular adjustment horizontally relative to the longitudinal movement of the bed comprising, a work supporting shaft pivotally supported between the head and tail stocks of the bed, a wheel loosely mounted on the shaft, an indexing gear seeured to the shaft, a spring pressed plunger mounted on the wheel and engaging between the teeth of the indexing gear, a stationary guide bar adapted for angular adjustment vertically relative to the longitudinal movement of the work shaft, an arm connected with the loosely mounted'wheel and projecting over the guide-bar whereby longitudinal movement of the bed turns the work-shaft, and 1lgieaus for adjusting the angle of the guide- In testimony whereof, I sign this specification in the presence of two witnesses.

1 WLTUN O. CROSS. Witnesses:

EMENS B, Wrsnnn, Cmmns E, Wrsnnn. 

